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Plants from the Brassicales order are known for the presence of a glucosinolate–myrosinase link, which is an important protection strategy against multiple stressors. The main goal of this study was to investigate the presence of the myrosinase enzyme and reveal the myrosin cell ultrastructure in the vegetative organs of nasturtium. The presence, localisation and expression of the enzyme myrosinase type 1 (TGG1) at different developmental stages of Tropaeolum majus L. (nasturtium) were investigated using immunohistochemical and immunofluorescent techniques. The expression of myrosinase was detected in the vegetative organs of T. majus. During plant development, within four consecutive weeks, a decrease in myrosinase expression was noticed in all studied plant organs. The location of greater myrosinase accumulation and activity is shown to be the root, contrary to the nasturtium stem and leaf, where we found the lowest myrosinase expression. Transmission electron microscopy was used to reveal the ultrastructural features of the myrosin cells of nasturtium. Myrosin cells are usually scattered between parenchyma cells and S-cells. Mostly, they are rectangular or slightly elongated in shape and can be recognised by an electron-dense large central vacuole and an expanded rough endoplasmic reticulum. The results of this study provide new data on myrosin cell morphology and the expression pattern of myrosinase in T. majus. [ABSTRACT FROM AUTHOR]

Olive growing in Croatia has a long tradition and is of great economic and social impact. The present study includes a set of 108 tree samples (88 samples corresponding to 60 presumed cultivars and 20 trees of unnamed ones) collected from 27 groves in the entire olive growing area, and is the most comprehensive survey to be conducted in Croatia. The genetic diversity, relationships, and structures of olive plants were studied using eight microsatellite loci. All loci were polymorphic and revealed a total of 90 alleles. A total of 74 different genotypes were detected that were subjected to further diversity and genetic relationship studies. The Fitch–Margoliash tree and Bayesian analysis of population structure revealed a complex relationship between the identified olive genotypes, which were clustered into three gene pools, indicating different origins of Croatian olive germplasms. Excluding the redundant germplasms, 44 different genotypes among the sampled trees of well-known cultivars and 16 new local germplasms were identified. In addition, we provide the etymology of 46 vernacular names, which confirms that the vast majority of traditional Croatian cultivars have common and widespread names. The results presented herein underline the importance of safeguarding local cultivars and conducting continuous surveys. [ABSTRACT FROM AUTHOR]

The histological structure and histochemical characteristics of the digestive tract of five specimens of salema porgy (Sarpa salpa, L.) were analysed using haematoxylin-eosin, Alcian blue/PAS and orcein-Giemsa staining techniques. The digestive system of salema porgy consists of esophagus, stomach and intestines with associated organs such as liver, pancreas and gallbladder. The wall of esophagus, stomach, intestines and gallbladder has four distinctive layers: the mucosa, the submucosa, the muscular and outer layer, serosa or adventitia. The mucosa consists of two different layers: epithelium and lamina propria. Mucosa of the upper part of the digestive system is layered by single squamous epithelium, while those of lower part of the digestive system is layered by single columnar epithelium. The submucosa is a layer made of connective tissue and blood vessels. In most parts of the digestive system the muscular layer consists of two parts: circular and longitudinal. The exception is the muscular layer of the stomach fundus which has three layers: inner, medium and outer. The outermost layer in the esophagus is adventitia made of connective tissue, blood vessels and nerves. In the stomach, intestines and the gallbladder this layer is replaced by serosa. Histochemical analysis has shown that mucosal cells in all parts of the digestive tube contain acid mucopolysaccharides (MPS). The liver consists of hepatocytes separated by sinusoidal capillaries. The pancreatic tissue is scattered along the liver parenchyma and along the wall of pyloric caeca. The present study is the first record on digestive system histology of salema porgy showing that it is congruent to its feeding habits. [ABSTRACT FROM AUTHOR]

The study aimed to determine whether the exposure to chronic stress and/or performance of gonadectomy might lead to disturbance in the expression of connexin (Cx) 37, 40 and 43 in the spinal cord (SC), as a potential explanation for sex differences in stress-related chronic pain conditions. After the rats were sham-operated or gonadectomized, three 10-day sessions of sham or chronic stress were applied. Immunohistochemistry and transmission electron microscopy (TEM) were used to examine Cx localization and expression in the SC. The gonadectomy resulted in an increase of Cx37 expression in the dorsal horn (DH) of the female rats, but chronic stress suppressed the effects of castration. In male rats, only the combined effects of castration and chronic stress increased Cx37 expression. The influence of chronic stress on the DH Cx40 expression was inversely evident after the castration: increased in the ovariectomized female rats, while decreased in the orchidectomized male rats. We did not find any effect of chronic stress and castration, alone or together, on Cx43 expression in the DH, but the percentage of Cx43 overlapping the astrocyte marker glial fibrillary acidic protein (gfap) increased in the male stressed group after the castration. In conclusion, the association of the chronic stress with sex hormone depletion results in disturbances of the SC Cx expression and might be a possible mechanism of disturbed pain perception after chronic stress exposure. [ABSTRACT FROM AUTHOR]